“Tails From The Field” is a series of true stories from Chad Culp’s experience in the field of professional dog training. Some details, such as names and breeds, may have been changed for privacy protection.


Voicemail: “Hi Chad, Do you remember Morton? You helped us when he was a puppy but we really need your help again because he bit someone.” 

Morton The Mastiff Puppy

Our story starts with a phone call from an out of state breeder who was calling trainers in the Bay Area to find one for Morton, a mastiff puppy, who would soon be arriving at his Silicon Valley home. She insisted that the owners get professional training and was very adamant that the training must be traditional, choke chain sort of training. At the time, I thought it was great that the breeder cared so much about her pup’s training but, looking back, it should have been a red flag. Anyhow, we talked and I explained that I use treats along with corrections in a balanced style of training. She seemed ok with this and said that the client would be contacting me for regular weekly lessons, probably multiple lessons per week. 

I met with the client and we did some lessons but it turned out to be less regular than the breeder had suggested. I only saw Morton about 6 times over a three-month period but this was all they scheduled with me and I didn’t feel it was my place to insist they do more. Plus, things were going great. Morton was about 5 months old when they stopped booking lessons with me. They had hired a dog walker and were taking Morton to a doggie daycare regularly, so he was getting plenty of exercise and socialization. With all of that help, they probably figured they didn’t need a trainer anymore. This is totally common, most people do not do private lessons for months on end, so I thought nothing of it. All seemed good, so, assuming no news was good news, I checked Morton off as a puppy training success. Of course, it ain’t over ‘til it’s over, so our story continues.  

The Head Halter and The Irate Breeder 

A couple of months later I got a call from the breeder who was irate because the owner had sent her a picture of Morton wearing a head halter (gentle leader). “I thought I made it clear that my dogs needed to be trained with a choke chain!” She exclaimed. I calmly explained to her that I had not seen them in a while and that I had started on a martingale collar and then transitioned to a prong collar. “If they started using a head harness, it was not recommended by me.” I said. “Maybe you should call them instead of me.” 

She called me back the next day to let me know that she had made a mistake, the photo was not of Morton, it was one of the other dogs from his litter. I appreciated the call back but the reason I am mentioning this incident has nothing to do with head halters, it has to do with the fact that she was breeding dogs that came from a particular line of mastiffs with strong guarding instincts. In other words, not the laid back, lovable, “gentle giant” sort of mastiff that Morton’s owners had owned previously. The reason that she was pushing so strongly for dominant dog style training was because, without strong leadership, this line of dogs could develop dominance-based aggression issues. So, on the one hand, she meant well, but on the other hand, she should never have sold them a puppy because they were not in need of a guard dog and they were light years from being the type of people that would dominate their dog. Anyhow, I never heard back from the breeder and the owner did not contact me for more lessons, so, again, I mistakenly assumed that no news was good news. 

Morton Develops Aggression 

If you recall, the last time I had seen Morton he was 5 months old and everything was going great. A year and a half later, when he was almost 2 years old, I got called back in because Morton had bit a staff member at the daycare when she reached over the gate to pet him. Apparently, the bite was bad enough that she had to go to the hospital for stitches.  

In case you’re wondering, no, this bite did not just come out of nowhere. It turned out that no news had not been good news. Morton’s adolescence had come with multiple red flags that I was not kept in the loop about. He had snapped at a few people out in public when they tried to pet him, he got attacked by another intact Mastiff at some dog related event, he developed reactivity towards dogs on his walks and they had problems at the vet’s office where he snapped at the staff and was guarding his kennel. 

How did things get so out of control, you ask? Basically, there were too many cooks in the kitchen and none of them were following my original recipe. 

The Cooks Who Spoiled The Soup

The Breeder: Remember how she had very strong opinions about how her dogs should be trained? Well, she also made them sign an agreement to keep him intact until he was 18 months old. This is a common practice for the benefit of the dog’s physical development; however, it should have also been considered through the lens of the dog’s mental and social development. If we look at the situation holistically, we find that the doggie day care would not allow dogs over 6 months if they were still intact. We also find that this was Morton’s main, if not only, source of socialization with other dogs, as well as a major source of his daily exercise. So, from 6 months old to 18 months old (a whole year) Morton was essentially stuck at home all day rather than going to daycare. This halted a majority of his socialization through the adolescence period (a.k.a. the teenage phase). 

No, I’m not blaming the breeder, not entirely anyhow, I am simply pointing out the dangers of strong opinions and blanket statements that are not put in context with the whole situation. The breeder would probably argue that there are other ways to socialize dogs that don’t require neutering, which is true, but, in Morton’s case, the owners were very busy and didn’t realize how important it was to continue his socialization through adolescence. They, like so many puppy owners, probably just assumed they could pick back up where they left off once he was neutered. To the contrary, 6-18 months of age is a critical period in a dog’s development and you really don’t want to drop the ball during that time. 

The Dog Walker: Morton was no longer going to daycare but they had hired a professional dog walker, so they probably figured it would be fine because he was getting walked every day. However, the dog walker didn’t like prong collars and, instead, used a nylon slip lead held high up on the neck. Morton rapidly developed some aggressive behavior on his walks at this time, so the owner thought maybe the slip lead was causing it. Hmm? This needs a deeper dive because correlation does not necessarily mean causation. I’ll circle back to the slip lead question in a minute.  

The Doggie Daycare: This particular place was run by people with the “all positive” mindset and they only allowed Morton to come until he was 6 months old, due to being intact. At 18 months, after neutering, Morton was allowed to come back to daycare and got into a scuffle with a dog. They took him out of the social area and put him into his own kennel. They couldn’t enter the kennel or get him out because he was behaving aggressively. This is how he wound up biting a staff member who reached over the gate to pet him. 

To sum that all up, I had started a recipe for raising and training Morton and it was going very well. Structured walks and socialization in public places, long duration heeling, long line exercises, basic obedience training, the long down, you know, all the basic, fundamental stuff. Then all these other folks took over and, apparently, didn’t follow my recipe at all. Is there a single person to blame for Morton’s aggression? No, but there were clearly too many cooks in the kitchen. 

Let’s ask a few questions: 

  • What if the breeder had not insisted Morton remain intact, and he therefore stayed in daycare the whole time? 
  • What if the breeder had not sold a dog bred for guarding and protection to a family that just wanted a happy-go-lucky dog? 
  • What if they had hired an open-minded dog walker, rather than one that was opposed to prong collars, and had me train the dog walker to handle Morton properly? 
  • What if they used a doggie daycare that wasn’t “all positive” and actually knew how to correct dogs for misbehaving rather than sticking them in a kennel for a “timeout”? Or at least one that trained staff members to NEVER reach over a gate to pet the dogs. NEVER, NEVER, NEVER!!! 
  • What if they had stuck with our regular training sessions like the breeder had suggested?

Obviously, Morton’s owners were well intended. They had purchased him from a reputable breeder, hired a trainer, a dog walker and a doggie care service. They basically hired an entire team to help raise their dog! However, when you hire “a team” you need to be the team leader, you need to be sure that they are actually working as a team, otherwise, it’s just a case of too many cooks in the kitchen. 

Did The Slip Lead Cause Morton’s Aggression?

Morton’s aggression started happening right around the time that they had stopped training with me and the dog walker had started doing most of Morton’s walks, so the owner thought maybe it was the slip lead that was causing it. Then, he talked to the doggie day care people and they concurred, saying that they were sure that was the problem and recommended a harness. It’s funny to me how quickly people will jump to conclusions like that. First of all, the daycare people were “all positive” so it is virtually guaranteed that they are massively biased. Second of all, this all coincided with Morton coming of age and being kicked out of daycare for being intact. Third of all, it’s not the tool, it’s how the tool is used that matters. There’s a saying in dog training that goes something like, “It’s not the tool, it’s the fool.” 

Anyhow, I don’t see how the slip lead itself could have possibly caused the aggression. I would, however, be willing to bet that the slip lead was used improperly which means that tension in the leash was causing aggression. Most people, even professional dog walkers, tend to allow the dog to walk with a slightly tense leash regardless of the type of collar. Most do not even realize what the definition of a tight leash really is and therefore, if you asked them, they would claim that they do not walk dogs on a tight leash but, with very few exceptions, they do and don’t even realize it.  

Regardless of the type of collar, tight leashes cause frustration and agitation, which can lead to aggression. That, combined with all the other factors, is simply a bad recipe with no single source to point a finger at.  

Morton’s Rehabilitation Training 

Remember, I hadn’t seen or heard from them since Morton was a pup and now, I was called back in and briefed on all the above situations. Basically, what I came back to find was that all the foundational training I laid was completely gone. He wouldn’t even sit on command. The owner didn’t remember any of the physical pressure techniques for following through on commands. They couldn’t get him to stop biting on the leash. He would grab jackets, towels or blankets from people’s hands and wouldn’t let go, wouldn’t drop the ball on command, pulled on leash, was walking in front rather than in heel position, etc. Oh yeah, did I mention that he was ginormous at that point! The good news is that he didn’t show any aggression towards me and I was able to handle him without a struggle. Apparently, he remembered me. 

What did I do? Well, for starters, I put the prong collar back on and reestablished some actual control over this giant dog. Once we had become reacquainted with some affection, treats, leash work and a quick review of basic obedience, I did some long line work and some socialization with my dog, Banjo. Everything went fine, I didn’t see any issues but we were also outdoors with plenty of space. This certainly didn’t mean Morton would be fine at an indoor daycare run by “positive” people but things looked hopeful.   

Next, we took Morton to a doggie daycare that was run by a friend of mine who actually knew how to control the dogs. He was allowed to run free with about 20 dogs and did fine. However, this place was large and outdoors and only doing me a favor by temperament testing Morton, they were not accepting new clients at that time. 

We tried another doggie daycare that was indoors and Morton immediately became aggressive towards another big dog. I was able to correct him quickly but the girl working there was screaming bloody murder. Clearly, that place wasn’t going to work. 

Morton needed to get back on track with some regular training and rehabilitation. The owners were in way over their heads and very much in immediate need of a place to board him because they had busy work schedules and travel plans coming up. I do not offer boarding so I was at the end of my ability to help them. I referred them to another trainer who offered training as well as boarding. The last I heard; all was going well. 

Moral of the Story

Don’t assume that just because someone is a “professional” that they are good. 

Don’t ignore red flags. Morton had started showing signs of aggression within a couple months of my last lesson with him but they let a year go by before calling me. 

Don’t drop the ball during “The Teenage Phase”. There is a lot of attention put on early socialization these days, which is super important, but let’s not forget the importance of continuing our three paths of socialization through adolescence and into adulthood. 

Genetics matter! Choosing the right dog for yourself and your family in the first place will save a lot of hassle and heartache. For example: If you want a social butterfly, don’t get a dog with the genetics of a guard dog. Doing a little breed research before getting a dog is always a good idea but also realize there are variations within breeds, as was the case with Morton. 

If you are going to hire a team of helpers, choose your team wisely and be sure they actually function as a team. If you are having success with a certain tool or technique, don’t hire team members who are unwilling to use it. If the team does not work as a team, it will simply be a jumble of cooks spoiling the soup. 

Chad Culp – Certified Dog Trainer, Canine Behavior Consultant, Owner of Thriving Canine. 

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